docs: def export(self, nidm_version, export_dir):
          """
          Create prov entities and activities.
          """
          num_peak = ()
          if self.num_peak:
              num_peak = ((NIDM_MAX_NUMBER_OF_PEAKS_PER_CLUSTER, self.num_peak),)
  
          # Create "Peak definition criteria" entity
          self.add_attributes((
              (PROV['type'], self.type),
              (PROV['label'], self.label),
              (NIDM_MIN_DISTANCE_BETWEEN_PEAKS, self.peak_dist)
              ) + num_peak)